Accumulator



Feb. 6, 1951 E. D. JoHNsoN ETAL ACCUMULATOR Filed April 26, 1947 CARL F. WALL BY ATTORNEY.

Patented Feb. 6', Y11951 `Wall, .Mariolav Ill.,-assignors toaWagner Electric Corporation,` St. Louis, Mo.,la-. corporation .of

' Delaware Application April 26, 19427,- Serial No. 744,140

(Cl. 13S- 30) SfClaims.

Qur invention lrelates to .devices commonly -re- .ferledto as accumulators for storing fluidun'- der pressure for the 'operation of vehicle brakes and; other' devicesA and:4 invY its more Vspecific aspects midi-rented to:` an accumulator embodying` a plu- .ral'ityf of. Aloa-gs containing a, compressible medium, suclrasair `or aninert gas, and b-yv means of which .pressurezis:maintained on vthe ,operating fluid in the accumulator.

.Onezof-the objects of our invention istozsoconstruct :the bags of-the accumulator and associate them` with/the containing walls of the' accumulator.-.unit, thatuwhen: fluid vto'be stored under pressures forced into `the unit, a uniform .invagination ofthe bagswill oscura-nd .there will be no entrapment of uidlbetween a portion of the wallsjofthe bags and awall of the containing unit eitherduring. the storing or :discharging ofwthe operating fluid.

Another object, is lto provide an: accumulator unit `embodying rtwo bags or bladders, ythe closed ends ofrvwhi'ch, when the' bladders arezcharged with the compressible medium 'and the unit is not charged with operating fluid, engage each other along approximately the centerline of theaccumulator unit and at which line a narrow circumferential slot is provided'for the. delivery and discharge of the operating fluid. Theadvantages of V.the construction'fj'ust indicated will be more fully pointed out in. the' following description.

The drawing shows a vertical sectional view of an accumulatorxunit whichfcomprises a cylindricalY casing. consisting of two identical. sections` I and 2 and a ring 3 which ring securessaid sections together with their adjacent ends 4 spaced apart whereby a vcircum-ferential narrow-slot 4 is formed throughwhich operating pressure fluid mayrfbe forced into;I the casing lfrom the circumferential groove 'formed on Athe innerface of the-connecting ring 3. By means of an inlet fitting, conduit 6 for supplying operating pressure uid is placed in communication with groove and slot 4.

In each casing section is positioned a bag or bladder 'l made of flexible material having a normal shape as shown in the drawing except that the normal diameter of each bag is slightly larger than the interior diameter of the casing section in which it is contained whereby when installed in position the parts of the bag bearing on the wall of the container are maintained in slight pressure engagement therewith by reason of the resilience of the bag material. The outer ends of the bags are each provided with a closure located in this reduced portion. Each closure comprises a disc 8 and a plate 9 between the parts oi which ythe bead- I Garoundithe bagropeningris. clamped.

Thesel :closure elementsearel clamped together-by '.ttin'gs -i 2 andv are :retained inhpositifonv by caps 13.

Arfluid seal vlltiformsra huid-.tight lc'on'nectiorinbetween-.the periplieryzof plate eland-theinnerwall cf the end ofthe 'casingsection.

.Thefttings' l'linvv the' bag closures .are.connected. 'together by cond-uitg. l lll and. d'5. through an inlet valve' it". fo'rlthe .compressible flu-.id Ine.- dium` to bev supplied to the interior oil the-mags, the bag vchambers'. being interconnected-.-fthrough :the: conduits so .that equal; pressures-lare developed'in the :bag-*sii when charging Vthem;.thro'ugh Ivalve it., The norma'l positionioffthexclosedends "or loottom'wallsk of `the bags;v whenI no operating fluidiris contained: in". the acoumulatorf'isflthat shown in the drawing. In other WOrdathefmTeeting linexof. the outerrsurfaces oi these `closed ends is normally substantially .inx alignment withl slot 4. "This vslot is so narrow. that underrnaximum pressure of the compressible fluid. medium con- .tainedinthebags,V thefbagi material will notice extruded into th'exslot even though. a portion thereof. should. at any time lie" acrossa partfof the 'slot.

When"operating fluid kis forced into the: accu` mulator through vconduit 6, .circumferential groove 5,.'and` slot 4, the air or other gaseous contentfof the bags is compressed, the `bottorn'wal-ls of the? .bags beingflexedasi indicated in thedraw-- ing.

By the useof two bagsin lieuof a singlebag in an accumulator unit .of a 4particular capacity relatively small peripheral areas ofA each bag-.will be=withdrawn from contactwith. the casing walls when lthel unit is fully charged with operating iiuid and,v therefore, .the likelihood of ventrapment of fluid:in.a localized area between the bag@ and container wall is very g-reatly decreased; and in a two bag structure with a peripheral supply and discharge slot for the operating fluid located at the center of the unit no special means is required to prevent entire blocking of the discharge for the operating uid by the bag material under any operative condition.

Having fully described our invention, that which we claim as novel and desire to protect by Letters Patent of the United States is:

l. A pressure accumulator comprising a casing having oppositely disposed openings, two flexible bags in the casing for receiving gas under pressure, each bag having an inlet end secured in pressure-tight relation with the inner surface of the casing at one of said openings, the two bags being shaped soas to substantially 1111 the space in the casing when under zero pressure conditions, and means for introducing pressure uid into the casing at a point between said openings.

2. A pressure accumulator comprising a casing and two fiexible bags therein for receiving a compressible medium, each of the bags having an opening therein through which fluid passes when entering or leaving the bags, said bags having their major portions lying in Contact with the inner surface of the casing and having bottom walls positioned adjacent each other when the ycasing contains no charge of pressure fluid, and means including a circumferential slot in the casing through which to introduce pressure uid into said casing at a point adjacent said last mentioned position of said bottom walls.

3. A pressure accumulator comprising a casing and two bags of resilient material therein for receiving a compressible medium, said bars having major portions of their surfaces in pressure contact with the interior surface. of the .casing and having bottom walls facing each other and located approximately at the center of the casing when the casing contains no charge of pressure fluid, means for charging the bags at equal pressures with a compressible medium, and means including a circumferentially disposed slot in said casing through which to introduce pressure fluid into said casing at its central portion.

4. A pressure accumulator comprising a casing having a circumferentially disposed slot through which to introduce pressure fluid into said casing at its central portion, two bags made of a resilient materialin said casing for receiving a pressure fluid and having bottom walls, a fluid under pressure to be introduced into said bags from an external source, said bags under conditions of zero pressure having major portions of their surfaces in pressure Contact with the interior surface of the casing and having their bottom walls facing each other and located approximately at the center of the casing when the casing contains no pressure fluid, a second pressure fluid to be introduced in said casing through said slot, and at least one of said pressure fluids being capable of occupying a space inversely proportional in volume to the pressure applied thereto.

5. A pressure accumulator comprising a pair of cylindrical members, each member having openings at each end thereof, means for connecting one end of one member to an end of the other member to form a casing provided with a circumferential slot between the members and so that the casing is open at its opposite ends, two flexible bags in said casing each having an open end for receiving a compressible medium, each of said open ends being secured in pressure-tight relation with the inner surface of the casing at one of said openings, and means for introducing pressure uid into the casing through said slot.

6. A pressure accumulator comprising a pair of coaxially oriented cylindrical members, each member having openings at each end thereof, a ring provided with an internal circumscribing groove and fitted around and joined in pressure-tight relationship to the adjacently disposed ends of said members so as to form a single open ended casing and assembled so so as to provide a circumferential slot between the cylindrical members, said slot aligned with said groove to p-lace same in communication with the interior of said casing, two ii'exible bags in said casing for receiving a fluid medium and each having an open end and a bottom Wall, each of said ends being secured in pressure-tight relation with the inner surface of the casing at one of its openings and with the bottom walls adjacent to each other and in substantial alignment with said slot, and means for delivering pressure uid into said casing through said slot to compress the fluid medium in said bags.

'7. A pressure accumulator comprising a casing of circular cross-section having openings at opposite ends and provided with a narrow circumferential slot between its ends and formed in the inner .surface of the casing, two flexible bags in said casing each having an open end for receiving a compressible medium, each of said open ends being secured in pressure-tight relation with the inner surface of the casing at one of said openings; and means for introducing pressure fluid into the casing through said slot.

8. A pressure accumulator comprising a casing of circular cross-section having openings at opposite ends and provided with a narrow internal circumferential slot, two iiexible bags in saidzcasing each having an open end for receiving a compressible medium, each of said open ends being secured in pressure-tight relation with the inner surface of said casing at said openings, means circumscrib-ing said casing so constructed and arranged with respect to said casing as to form a circumferential fluid passageway in communication with said narrow circumferential slot; and means for introducing pressure fluid into said passageway.

. EDWARD D. JOHNSON.

'CARL F. WALL.

REFERENCES CITED The following references are of record in the file of this patent:Y

UNITED STATES PATENTS Number Name Date 2,283,180 -Ellinvvood Aug. 21, 1945 2,390,319 Overbeke Dec. 4, 1945 

